<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    function fn(){
		return new Promise(resolve=>{
			setTimeout(()=>{
				resolve(100)
            })
        })
    }
	fn().then(value=>{
		console.log(value);
    })
</script>
</html>